It is known to have endless belt conveyor assemblies which are side-flexing. Usually, this construction is made by providing apertures in the eye parts perpendicular to the travelling direction. By overlapping the eye parts of two adjacent chain links, and inserting a transverse rod through the apertures, thereby connecting two adjacent chain links in a hinge-like manner, the two adjacent chain links will be able to flex relative to each other due to the possibility of the rod to move in the elongated shape of the overlapping apertures.
Such prior art constructions are known from for example EP 427337, EP 1306323 and others.
Common for the prior art endless belt conveyor is that it comprises a number of drawbacks. When conveyors are to transport food stuffs, either in raw or manufactured form, there are varying degrees of requirements to the hygiene levels which must be maintained for all equipment involved in the processing of food stuffs. Especially for fresh food stuffs it is important to have an extremely high level of hygiene in order to avoid contamination of the food stuffs from residue stuck in the belt construction, or other sources arising from an inability to satisfactorily clean and disinfect the endless belt conveyor.
Another serious drawback of conveyors of this type is the fact that as the conveyors are loaded and going through a curve, a substantial force will be induced in the outer part of the conveyor belt where the main part of the tension arises due to the pulling forces propelling the endless belt conveyor. For this purpose, a number of solutions have been proposed where reinforcement plates, sometimes in the shape of steel plates, are arranged in the outer sections connecting adjacent chain links such that these steel links will transfer the substantial forces arising when such an endless conveyor belt flexes to one side or the other.
It has also been suggested to reinforce the transverse rods such that the rods will be able to transfer the load from one flexing link to the adjacent link. However, when the transverse rods are made from plastic materials, the wear and tear in the transverse rods historically has shown that the life expectancy of such rods is very limited, which again results in increased maintenance costs, and extended periods of down time for the conveyor. By replacing the plastic transverse rods with steel rods as also suggested in the prior art, the wear and tear is transferred from the rods to the eye parts integral with the links such that, eventually, the eye part will be worn down whereby the entire link needs to be replaced.
Returning to the issue of hygiene, it has proven very difficult to thoroughly clean the apertures in which the transverse rods are arranged. This is due to the fact that the apertures have a limited size, but still provide play for the transverse rods such that the side-flexing capabilities of the entire conveyor belt may be provided in a substantially effortless manner, i.e. such that no substantial friction arises in the eye parts which could lead to heat generation, and deterioration of the plastic material. This play and the oversize allows for foreign matter, for example organic residue originating from the materials being transported on the conveyor, to become lodged, and which will only be removed during the cleaning process when particular care is exhibited. The residue organic material will give rise to bacteria growth, which may cause contamination of the articles transported on the conveyor belt which, in turn, might have serious complications for the end user.